Common names: sidewinder, horned rattlesnake, sidewinder rattlesnake, more.

Crotalus cerastes is a venomous

Venomous snake

"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...

 pitviper

Crotalinae

The Crotalinae, commonly known as "pit vipers" or crotaline snakes, are a subfamily of venomous vipers found in Asia and the Americas. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on either side of the head...

 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 found in the desert regions of the southwestern United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and northwestern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. Three subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 are currently recognized, including the nominate subspecies described here.

Description

A small species, with adult specimens measuring between 43 cm and 76 cm (17 to 30 in) in length. According to Campbell and Lamar (2004), most adults are 50–80 cm (19.8 to 32 in) in length. The females are larger than the males, which is unusual for this group of snakes.

Midbody there are usually 21 rows of keeled

Keeled scales

Keeled scales refer to reptile scales that, rather than being smooth, have a ridge down the center that may or may not extend to the tip of the scale, making them rough to the touch...

 dorsal scales

Dorsal scales

In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales.When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17...

. In males there are 141 or fewer ventral scales

Ventral scales

In snakes, the ventral scales are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that contacts the paraventral row of dorsal scales on either side...

; in females 144 or fewer. Sometimes referred to as the horned rattlesnake because of the raised supraocular scales

Supraocular scales

In scaled reptiles, supraocular scales are scales on the crown immediately above the eye. The size and shape of these scales are among the many characteristics used to differentiate species from each another....

 above its eyes. This adaptation may help shade the eyes or prevent sand drifting over them as the snake lies almost buried in it.

The color pattern consists of a ground color that may be cream, buff, yellowish brown, pink or ash gray, overlaid with 28-47 dorsal blotches that are subrhombic or subelliptical. In the nominate subspecies, the belly is white and the proximal lobe of the rattle is brown in adults. Klauber and Neill describe the ability of this species to display different coloration depending on the temperature—a process known as metachrosis.

Common names

Sidewinder, horned rattlesnake, sidewinder rattlesnake, Mojave Desert sidewinder (for C. c. cerastes), sidewinder rattler.

Geographic range

In the southwestern United States, this species is found in the desert region of eastern California, southern Nevada, southwestern Utah and western Arizona. In northwestern Mexico, it is found in western Sonora and eastern Baja California. Sonora is a northwestern state and the portion of Mexico bordering California and Arizona. Baja California is the peninsula south of California and west of Mexico.

Conservation status

This species is classified as Least Concern (LC) on the IUCN

World Conservation Union

The International Union for Conservation of Nature and Natural Resources is an international organization dedicated to finding "pragmatic solutions to our most pressing environment and development challenges." The organization publishes the IUCN Red List, compiling information from a network of...

 Red List of Threatened Species

IUCN Red List

The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...

 (v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because it is unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend is stable. Year assessed: 2007.

Behavior

The common name sidewinder is an allusion to its unusual form of locomotion, which is thought to give it traction on windblown desert

Desert

A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...

 sand, but this peculiar locomotor specialization is used on any substrate that the sidewinder can move over rapidly. As its body progresses over loose sand, it forms a letter-J shaped impression, with the tip of the hook pointing in the direction of travel. Sidewinding

Sidewinding

Sidewinding is a type of locomotion unique to caenophidian snakes, used to move across loose or slippery substrates. It is most often used by the Saharan horned viper, Cerastes cerastes, and the sidewinder rattlesnake, Crotalus cerastes, to move across loose desert sands, but it is also used by...

 is also the primary mode of locomotion in other desert sand dwellers, such as the horned adder (Bitis caudalis

Bitis caudalis

Bitis caudalis is a venomous viper species found in the arid region of south-west Africa. Easily distinguished by the presence of a single, large horn-like scale over each eye. No subspecies are currently recognized.-Description:...

) and Peringuey's adder (Bitis peringueyi

Bitis peringueyi

Bitis peringueyi is a venomous viper species found in Namibia and southern Angola. No subspecies are currently recognized.-Description:A small snake with an average length of 20–25 cm and a maximum recorded length of 32 cm....

), but many other snakes can assume this form of locomotion when on slick substrates (e.g., mud flats).

The species is nocturnal during hot months and diurnal

Diurnal animal

Diurnality is a plant or animal behavior characterized by activity during the day and sleeping at night.-In animals:Animals that are not diurnal might be nocturnal or crepuscular . Many animal species are diurnal, including many mammals, insects, reptiles and birds...

 during the cooler months of its activity period, which is roughly from March to November (probably longer in the southern part of its range).

Juvenile Sidewinders use their tails to attract lizard prey (see video: http://www.open2it.com/videos/62-animal-behavior/162-caudal-luring-in-the-sidewinder-rattlesnake.html), a behavior termed "caudal luring

Caudal luring

Caudal luring is the use of tail movements employed by a predator to attract prey animals. It is a form of mimicry classified formally as aggressive mimicry, but perhaps better described by the term feeding mimicry. The behavior is employed by a number of snake species and allegedly by two lizards,...

". Adult Sidewinders lose this behavior as they make the transition from lizard prey to their primary diet of desert rodents. Sidewinder juveniles appear to mimic both life stages of lepidopterans in their luring motions. Their fast luring motions resemble the fluttering of a moth and their slower tail movements resemble a caterpillar. Both movements have been observed to attract prey lizards.

Neonatal sidewinders engage in a remarkable type of behavioral homeothermy that has not been observed in any other type of snake. Following birth, the neonates mass together in their natal burrow. Most often, gravid females select an East facing, small diameter rodent burrow to birth in. For the first week or so of their lives, neonatal sidewinders literally plug the entrance to this burrow during daylight hours, forming a dynamic multi-individual mass that takes advantage of the hot exterior environment and the cool interior of the burrow to maintain an average aggregate temperature of 32°C (the optimal temperature for shedding). Experiments showed that the dynamic mass of neonates modifies the thermal environment at the burrow entrance such that the young can occupy a location that would ordinarily become lethally hot for an individual neonate (or even an adult). Because of the constant movements of the neonates, the aggregate assumes stable temperature properties reminiscent of a homeothermic organism (i.e., maintains tight temperature tolerance ± 2°C).

Reproduction

Females produce up to 18 young, with an average of about 10 per litter. Like most other viperids

Viperidae

The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...

, the young are born enveloped in thin embryonic membranes out of which they emerge shortly after being expelled from the mother. The young stay with their mother in a burrow for 7–10 days, shed for the first time, then leave their natal burrow. During this time, it is thought that the mother guards and protects them from predators.

Sidewinders mature at 2–3 years of age, are capable of reproducing annually, and give birth to live young. Some females skip reproductive opportunities. Some might even skip two years, if the food supply is scarce. Sidewinders mate in April through May and sometimes in fall. When the male and female mate, the male snake crawls along the female's back, rubbing her with his chin to stimulate or arouse her. The male then will wrap his tail around her tail and then will try to bring their clocque together. The clocque is a little flap that is near tail which is designed for mating and reproduction. If the female wants to mate, she will lift her tail and allow him to mate with her. The snakes can be mating for several hours, and if one of the snakes decides to move, the other is dragged along. Females might mate with several males in a season. Females give birth to 5-18 young in late summer to early fall. The young are born 6 to 8 inches long. The birth takes only 2 to 3 hours altogether. Within a few minutes after being born, the baby sidewinder escapes out of a thin transparent membrane. The young stay at their natal burrow for 7–10 days until they shed and then they disappear and have no future contact with their mother or their littermates. While the density of sidewinders can be up to 1 individual per hectare

Hectare

The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

, individuals rarely encounter each other except during mating season.

Sidewinders have an extraordinarily accelerated life cycle, with natural life expectancies of females of about five years. Males may live quite a bit longer (max known natural life span of 13 years). Sidewinders can live more than 20 years when well fed in captivity (even females). Thus, it appears that energetics factor heavily into natural female mortality, whereas predation might be the primary pressure on males. In the wild, females often die of post-birth exhaustion, but the lives of sidewinders are also cut short because of predation, diseases, and vehicle encounters.

Venom

These snakes are venomous, but possess a weaker venom than many other rattlesnakes. This, together with the smaller size of their venom glands, makes them less dangerous than their larger cousins. Still, any rattlesnake bite can be fatal and should be taken seriously and medical attention sought immediately.

Norris (2004) lists the following venom yields: 33 mg average and 63 mg maximum (Klauber, 1956), and 30 mg average and 80 mg maximum (Glenn & Straight, 1982). Brown (1973) gives a venom yield of 33 mg (Klauber, 1956) and values for mice of 2.6 mg/kg IV

Intravenous therapy

Intravenous therapy or IV therapy is the infusion of liquid substances directly into a vein. The word intravenous simply means "within a vein". Therapies administered intravenously are often called specialty pharmaceuticals...

, 3.0, 4.0, 2.3 mg/kg IP and 5.5 mg/kg SC for toxicity. With these figures, Brown calculated that the LD₅₀ for an adult human being weighing 70 kg would be 385 mg (SC).

Bites can cause pain, swelling, hemorrhagic bleb formation and ecchymosis

Ecchymosis

An ecchymosis is the medical term for a subcutaneous purpura larger than 1 centimeter or a hematoma, commonly called a bruise. It can be located in the skin or in a mucous membrane.-Presentation:...

. Any swelling is usually not particularly severe, but it can involve all of the affected limb as well as the trunk. Systemic symptoms can include nausea, dizziness, chills, coagulopathy

Coagulopathy

Coagulopathy is a condition in which the blood’s ability to clot is impaired. This condition can cause prolonged or excessive bleeding, which may occur spontaneously or following an injury or medical and dental procedures.The normal clotting process depends on the interplay of various proteins in...

 and shock. Klauber (1997) includes an account of a man who had been bitten on the first joint of the index finger of the right hand, with only a single fang penetrating. Although the bite itself was described as no more painful than a pin prick, a doctor was seen within about 25 minutes and 10 cc of antivenin had been administered, within 2.5 hours his entire arm had swelled and the pain was violent, "as if the arm were soaked in a bucket of boiling oil."

Ovine derived antivenom, CroFab, for North American pit viper envenomation has been widely available since 2001. Consultation with a local expert or regional poison control center should be obtained before administering antivenom. Previous antivenin (ACP) is no longer manufactured.

Subspecies

Subspecies	Taxon author	Common name	Geographic range
C. c. cerastes	Hallowell, 1854	Mojave Desert Mojave Desert The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...  sidewinder	In the United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district...  in the desert areas from northeastern Los Angeles County Los Angeles County, California Los Angeles County is a county in the U.S. state of California. As of 2010 U.S. Census, the county had a population of 9,818,605, making it the most populous county in the United States. Los Angeles County alone is more populous than 42 individual U.S. states...  and San Bernardino County, California San Bernardino County, California San Bernardino County is a county in the U.S. state of California. As of the 2010 census, the population was 2,035,210, up from 1,709,434 as of the 2000 census... , northward to southern Mono County, California Mono County, California Mono County is a county located in the east central portion of the U.S. state of California, to the east of the Sierra Nevada between Yosemite National Park and Nevada. As of the 2010 census, the population was 14,202, up from 12,853 at the 2000 census... , east across Nevada Nevada Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...  to Washington County, Utah Washington County, Utah As of the census of 2000, there were 90,354 people, 29,939 households, and 23,442 families residing in the county. The population density was 37 people per square mile . There were 36,478 housing units at an average density of 15 per square mile... , and south through Mohave County, Arizona Mohave County, Arizona Mohave County is located in the northwestern corner of the U.S. state of Arizona. As of the 2010 census, its population was 200,186, an increase of 45,154 people since the 2000 census count of 155,032. The county seat is Kingman... . Desert lowlands at elevations between 152 and 1,829 m.
C. c. cercobombus Crotalus cerastes cercobombus Crotalus cerastes cercobombus is a venomous pitviper subspecies found in an area that covers much of the eastern part of the Sonoran Desert in the southwestern United States and northwestern Mexico...	Savage & Cliff, 1953	Sonoran Desert Sonoran Desert The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...  sidewinder	In the United States from Yuma Yuma County, Arizona -2010:Whereas according to the 2010 U.S. Census Bureau:*70.4% White*2.0% Black*1.6% Native American*1.2% Asian*0.2% Native Hawaiian or Pacific Islander*3.8% Two or more races*20.8% Other races*59.7% Hispanic or Latino -2000:... , Maricopa Maricopa County, Arizona -2010:Whereas according to the 2010 U.S. Census Bureau:*73.0% White*5.0% Black*2.1% Native American*3.5% Asian*0.2% Native Hawaiian or Pacific Islander*3.5% Two or more races*12.7% Other races*29.6% Hispanic or Latino -2000:... , Pima Pima County, Arizona -2010:Whereas according to the 2010 U.S. Census Bureau:*74.3% White*3.5% Black*3.3% Native American*2.6% Asian*0.2% Native Hawaiian or Pacific Islander*3.7% Two or more races*12.4% Other races*34.6% Hispanic or Latino -2000:...  and Pinal Pinal County, Arizona -2010:Whereas according to the 2010 U.S. Census Bureau:*72.4% White*4.6% Black*5.6% Native American*1.7% Asian*0.4% Native Hawaiian or Pacific Islander*3.8% Two or more races*11.5% Other races*28.5% Hispanic or Latino -2000:...  counties in Arizona, southward into Sonora Sonora Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo.... , Mexico Mexico The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of... .
C. c. laterorepens Crotalus cerastes laterorepens Crotalus cerastes laterorepens is a venomous pitviper subspecies found in an area that centers around the Colorado Desert in the southwestern United States and northwestern Mexico.-Description:...	Klauber Laurence Monroe Klauber Laurence M. Klauber , was an American herpetologist, and was considered to be the foremost authority on rattlesnakes... , 1944	Colorado Desert Colorado Desert California's Colorado Desert is a part of the larger Sonoran Desert, which extends across southwest North America. The Colorado Desert region encompasses approximately , reaching from the Mexican border in the south to the higher-elevation Mojave Desert in the north and from the Colorado River in...  sidewinder	The desert areas in the United States from central and eastern Riverside County, California Riverside County, California Riverside County is a county in the U.S. state of California. One of 58 California counties, it covers in the southern part of the state, and stretches from Orange County to the Colorado River, which forms the state border with Arizona. The county derives its name from the city of Riverside,... , to Pinal County, Arizona, south to northwestern Sonora in Mexico, and northwest to northeastern Baja California Baja California Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North... . From the Colorado River Colorado River The Colorado River , is a river in the Southwestern United States and northwestern Mexico, approximately long, draining a part of the arid regions on the western slope of the Rocky Mountains. The watershed of the Colorado River covers in parts of seven U.S. states and two Mexican states...  to the desert foothills at elevations between 152 and 610 m.

In popular culture

In Quentin Tarantino

Quentin Tarantino

Quentin Jerome Tarantino is an American film director, screenwriter, producer, cinematographer and actor. In the early 1990s, he began his career as an independent filmmaker with films employing nonlinear storylines and the aestheticization of violence...

's Kill Bill

Kill Bill

Kill Bill Volume 1 is a 2003 action thriller film written and directed by Quentin Tarantino. It is the first of two volumes that were theatrically released several months apart, the second volume being Kill Bill Volume 2....

 movies, Michael Madsen

Michael Madsen

Michael Søren Madsen is an American actor, poet, and photographer. He has appeared in more than 150 films, most of them small independent films, though he has starred in central roles in such films as Reservoir Dogs, Free Willy, Donnie Brasco, and Kill Bill, in addition to a supporting role in Sin...

's character's codename is Sidewinder.

The American Heavy Metal band

Heavy metal music

Heavy metal is a genre of rock music that developed in the late 1960s and early 1970s, largely in the Midlands of the United Kingdom and the United States...

 Avenged Sevenfold

Avenged Sevenfold

Avenged Sevenfold is an American heavy metal band from Huntington Beach, California. Formed in 1999, the group consists of vocalist M. Shadows, lead guitarist Synyster Gates, rhythm guitarist Zacky Vengeance, bassist Johnny Christ....

 Made a song on the album City of Evil

City of Evil

City of Evil is the third studio album and first major label release by American metal band Avenged Sevenfold. The album was released on June 7, 2005 under the Warner Bros. Records label. Co-produced by Andrew Murdock, City of Evil contains a more hard rock and classic heavy metal sound than...

 called "Sidewinder".

American rock band

Rock Band

Rock Band is a music video game developed by Harmonix Music Systems, published by MTV Games and Electronic Arts. It is the first title in the Rock Band series. The PlayStation 3 and Xbox 360 versions were released in the United States on November 20, 2007, while the PlayStation 2 version was...

 Red Hot Chili Peppers

Red Hot Chili Peppers

Red Hot Chili Peppers is an American rock band, formed in Los Angeles in 1983. The group's musical style primarily consists of rock with an emphasis on funk, as well as elements from other genres such as punk, hip hop and psychedelic rock...

 mention sidewinders in Parallel Universe

Parallel Universe (song)

"Parallel Universe" is a promotional single by the Red Hot Chili Peppers from their 1999 album, Californication. Although it never was released as a tangible CD single, it charted on the US Modern Rock Tracks at number 37 during the week of March 24, 2001, and appeared on Greatest Hits.It is the...

.

External links

• Crotalus cerastes cerastes at California Reptiles and Amphibians. Accessed 5 February 2007.
• Crotalus cerastes at WildHerps. Accessed 5 February 2007.
• The Sidewinder at VenomousReptiles.org. Accessed 5 February 2007.
• Mojave Desert Sidewinder at Bird and Hike . com. Accessed 5 February 2007.